What should in a 1989 420 sel

Chances are that the plugs that came with the car are no longer made. You can go to the Bosch usa website and plug in your car to get a list of plugs as well as filters, O2 sensors, etc. Many people prefer the single electrode plug in Mercedes but I have been using the 2 electrode plug for about 2 years with no problems. If you want the single electrode scroll down as the multi-electrode ones are usually first.

Of course you could also check here at Fastlane parts.

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Good luck.






1998 E320 Wagon

Single and inexpensive copper for best bang for buck. Better metal for better life. Never go with multi-prong. Its all marketing and there are no proven gains. After all a flame front is a flame front. And there is this thing call physics that the marketing guys seem to ignore

I prefer copper (best conductor of electricity for the engine environment) NKGs. I will never use BOSCH plugs. They blow out too often. I also went a couple steps colder.

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1991 560 SEL / 185k miles
1992 750il / 17k miles - project car

I seem to do fine with Beru - basic, cheap, copper plugs.

I've also used Bosch but the basic copper ones seem hard to find now.

NGK are excellent too, I hear.

Also, leads, distributor cap and rotor should be MB original if possible. My leads are Beru and they seem good.

My motto is, "Don't economise on HT components".

RayH

If you go to a racing plug,they are copper and non resistor.

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1999 w140, quit voting to old, and to old to fight, a god damned veteran, deutschland deutschland uber alles uber alles in der welt

Auto Zone claims that the Bosch Platinum Plus are the best for my car.

Should I install thes plugs?

You may. They are only better in longevity. Replacing plugs every year can wear on the plug threads in the head more. Personally I dont care. I prefer to replace plugs more often since inspecting them can tell a story. But if you are not into replacing plugs every year or so, go platinum, etc. for longer life.

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1991 560 SEL / 185k miles
1992 750il / 17k miles - project car

I used on my 560 sec,after 10 minutes I trow them away.

NGK BP5ES if I recall. Autozone or oreilly have them .

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1984 300SD Orient Red/ Palomino
1989 560SEC
2016 Mazda 6 6 speed manual
1995 Ford F-150 reg cab 4.9 5speed manual

Those are what I'm running in the 420SEL.

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Cruise Control not working? Send me PM or email (jamesdean59@gmail.com). I might be able to help out.
Check here for compatibility, diagnostics, and availability!

(4/11/2020: Hi Everyone! I am still taking orders and replying to emails/PMs/etc, I appreciate your patience in these crazy times. Stay safe and healthy!)


82 300SD 145k
89 420SEL 210k
89 560SEL 118k
90 300SE 262k RIP 5/25/2010
90 560SEL 154k
91 300D 2.5 Turbo. 241k
93 190E 3.0 235k
93 300E 195k

Platinum's are all resistor plugs AFAIK. You already have a resistor in your spark plug connector, hence the need for non resistor plugs. Skip the platinums and follow the guys recommendations for one of the other good choices.

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90 300TE 4-M
Turbo 103, T3/T04E 50 trim
T04B cover .60 AR
Stage 3 turbine .63 AR
A2W I/C, 40 LB/HR
MS2E, 60-2 Direct Coil Control
3" Exh, AEM W/B O2
Underdrive Alt. and P/S Pulleys,
Vented Rear Discs, .034 Booster.
3.07 diffs 1st Gear Start

90 300CE 104.980
Milled & ported head, 10.3:1 compression
197° intake cam w/20° advancer
Tuned CIS ECU
4° ignition advance
PCS TCM2000, built 722.6
600W networked suction fan
Sportline sway bars
V8 rear subframe, Quaife ATB 3.06 diff

Don't get the Platinum ones, or Bosch. I had the same kind from Autozone and they were for crap. Went with $2.00 non-resistor copper and the car loves them!

420 benz, refer to your Owner's Manual for the proper spark plug. If the specified spark plug is no longer available, then rely on a cross-reference chart from another manufacturer to select an equivalent spark plug (heat range and seat configuration). Be sure to use a light coat of anti-sieze paste on the threads and torque properly, so as not to strip the head.

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Fred Hoelzle

Most newer plugs have a coating which eliminates the need for anti-sieze compound. I know this is true of Bosch probably other major manufacturers.

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Good luck.






1998 E320 Wagon